(1) Field of the Invention
A system for pressurizing a vessel with a non-compressible fluid and determining the pressure the vessel can withstand. In the present invention a flask is used as the vessel and a determination is made as to the internal pressure in the flask that corresponds to the yield point.
(2) Description of the Prior Art
There are a multitude of systems in use that determine the yield point of a flask. A large number of them correspond to the present invention in that water is used to form a variable pressure on the internal portion of the flask. The water pressure is increased and a determination is made as to the internal pressure of the water that causes deformation of the flask.
There are basically two methods of determining yield in a flask. The first method is called the volumetric expansion tank method, and the second method is called the dynamic pressure test unit method. The volumetric expansion tank method requires that the test be conducted on a fixed test bed in a controlled area, i.e., shop. It requires the use of a tank into which the test flask is placed. Both the tank and flask are filled with water. Additional water is then pumped into the flask to a predetermined level. If the flask should yield under the additional pressure, an amount of H.sub.2 O proportional to the expansion of the flask is measured in a Burrette attached to the test tank.
An improvement on the volumetric expansion tank method came with the dynamic pressure test unit. This method enables the test unit to be brought to the flask and eliminates the necessity for a test tank. The dynamic pressure test unit pumps water into the flask and records the proportional increase in pressure and volume on an x-y chart recorder. A yield in the flask is indicated by a non-linearity in the plot of pressure vs. volume on the recorder.